Advanced modulation formats for underwater visible light communications [Invited]

作     者：迟楠 石蒙 Nan Chi;Meng Shi

作者机构：Key Laboratory for Information Science of Electromagnetic Waves (MoE)Shanghai Institute for Advanced Communication and Data ScienceFudan University 

出 版 物：《Chinese Optics Letters》 (中国光学快报（英文版）)

年 卷 期：2018年第16卷第12期

页      面：20-30页

核心收录：

学科分类：0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：supported by the National Natural Science Foundation of China(NSFC)(No.61571133) the National Key Research and Development Program of China(No.2017YFB0403603) 

主　　题：Invited Advanced modulation formats for underwater visible light communications CAP QAM DFT 

摘      要：In this paper, we present a detailed comparison of applying three advanced modulation formats including carrierless amplitude and phase modulation（CAP）, orthogonal frequency division multiplexing（OFDM）, and discrete Fourier transform spread orthogonal frequency division multiplexing（DFT-S OFDM） in underwater visible light communication（UVLC） systems. Cascaded post-equalization schemes are suggested to compensate the system impairments. For the first time, a two-level post-equalizer is presented to mitigate the nonlinear effect and improve the system performance of UVLC. The first post-equalization is based on a novel recursive least square Volterra. These modulation formats are all experimentally demonstrated with corresponding digital signal processing（DSP） algorithms. The experimental results show that single carrier modulations including CAP and DFT-S OFDM can outperform OFDM. Our experiment results show that up to 3 Gb/s over a 1.2 m underwater visible light transmission can be achieved by using DFT-S OFDM 64 QAM and CAP-64. The measured bit error rate is well under the hard decision-forward error correction（HD-FEC） threshold of 3.8 × 10;.